The questions Roderick's asking are a few of the symptoms of dehydration. As for his actions, he's checking Max's eye for discoloration from lack of fluid intake, pinching his arm to test for elasticity (dehydration can cause your skin to not "bounce back" quickly when pinched), checking for a rapid heartbeat, and generally annoying Max.
Roderick's actions may seem odd, but the last thing he needs is an unknown agent passing out while they're on a rescue mission. In other words, he has his reasons. As to why no food or drink for Max, consuming food and drink from the fey realm will trap you in fey, remember? So if Max wants to go back home, he's going to need to keep things out of his mouth for the time being.
As for myself, please excuse any wonkiness in the middle panels. I conked my head good Saturday night and was still a little dizzy while finishing up the inking Sunday. Thanks guys.